Safety method for pyrotechnic launch devices

ABSTRACT

A method of providing safety for pyrotechnic launch devices of the type having a least one tilt detection device  10  &amp;  20 . Having a means of attaching said tilt detection device(s)  10  &amp;  20  to the launch device(s). Having a means of disabling launches from launch device(s) when at least one of said tilt detection device(s)  10  &amp;  20  detects that the launch device it is attached to is tilted beyond tolerances.

BACKGROUND-CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of Provisional Patent Application Ser. No. 60/181,961, filled Feb. 10, 2000.

BACKGROUND-FIELD OF INVENTION

[0002] The invention relates to pyrotechnic launching devices. Its purpose is to provide a method of halting launches of pyrotechnic devices, when the launch mechanism becomes oriented in a direction that may not be safe.

BACKGROUND-DESCRIPTION OF PRIOR ART

[0003] Currently the launch operator governs launch safety of electronically launched pyrotechnic devices. Launch units are placed in such a manner that the launch operator can see them. If the operator notices that a launching unit has moved to an inappropriate attitude the operator discontinues subsequent launches from that unit. While this method generally works, there is a chance that the operator may not notice that a launch unit has become oriented in an improper position. This may be due to smoke, negligence, or other circumstance. Additionally, if an electronic sequencing device is in use there may not be sufficient time to disable launches from miss-oriented launch units before the sequencer commands the next launch.

OBJECTS AND ADVANTAGES

[0004] Accordingly several objects and advantages of our invention are:

[0005] (a) to provide a means of automatically disabling launch units that become oriented in such a manor that safety may be compromised;

[0006] (b) to provide said disabling in a timely manor so that rapid launch sequences can be safely halted.

DRAWING FIGURES

[0007]FIG. 1 shows a schematic drawing of a typical implementation of a launch group having one launch unit with two tilt sensors.

[0008]FIG. 2 shows a schematic drawing of a typical implementation of a launch group having two launch units with two tilt sensors for each unit.

REFERENCE NUMERALS IN DRAWINGS

[0009] 10 Tilt Switches 20 Tilt Switches 12 Ground Input 22 Ground Input 14 Launch Signal Inputs 24 Launch Signal Inputs 16 Ignition Device 26 Ignition Device 28 Unit 1 29 Unit 2

SUMMARY

[0010] In accordance with the invention the method of providing safety for pyrotechnic launches comprises:

[0011] (a) At least one tilt sensing device.

[0012] (b) A means of attaching tilt sensing devices to pyrotechnic launch units.

[0013] (c) A means of interrupting electronically controlled launch circuits when one or more tilt sensing devices are detected as being out of the proper orientation.

[0014] Description—FIGS. 1-2

[0015] For the sake of this description several terms will be defined:

[0016] Launch unit—A set of electronically controlled mortars in which all the mortar tubes are fixed in relationship to each other. There may be from one to as many as practical mortar tubes in a launch unit.

[0017] Launch group—A group of launch units, which are placed in close proximity to each other. Close enough so that a problem with any launch unit in the group is deemed to be reason enough to halt all launches from all launch units in the group. A launch group contains one or more launch units.

[0018] Launch surface—The surface on which launch units are placed. Usually the earth, but may be other surface such as the surface of a barge.

[0019] The currently preferred sensor is a contact switch, which is normally electrically closed while the switch actuator is in contact with the launch surface. The preferred switch would become electrically open when the switch actuator looses contact with the launch surface. In a typical embodiment with one launch unit in a launch group (FIG. 1) a tilt switch 10 would be placed at each of two diagonal corners of the launch unit. The ground input 12 of the igniter circuit(s) for the launch group would pass through both of said switches 10 in series. Switch positions would be adjusted and locked in so that the ground would be completed while the launch unit is in the “proper attitude”. If at any time after initial setup the launch unit looses proper orientation, one or more of the tilt switches 10 would disable the ground side of the igniter circuit(s) so that no further launches could be triggered from that launch unit. As can be seen from the drawings when any of said switches 10 become electrically open the launch signal inputs 14 have no means of completing the circuit to ground input 12; thereby, disabling the ignition devices 16.

[0020] In a typical embodiment of a group with two or more launch units (FIG. 2) 28 & 29, tilt switches 20 would be attached to each launch unit as described above. The ground input 22 of the igniter circuits for the entire group would be wired through all tilt switches 20 in the group in series so that if any one of the launch units became miss-oriented further launches from the entire group would be disabled. As with the first description when any of said switches 20 become electrically open the launch signal inputs 24 have no means of completing the circuit to ground input 22; thereby, disabling the ignition devices 26.

[0021] Operation

[0022] With launch groups setup as described (in description section), if any launch unit became tilted, at least one of the two diagonal corners of the rectangular shaped launch unit would move away from the launch surface. When this happens the corresponding tilt detection switch 10 & 20 would loose contact with the launch surface, becoming electrically open. With any switch in the open position the entire launch groups ground would be open, preventing further launches from the group until the situation was rectified.

[0023] Conclusion, Ramifications, and Scope

[0024] Accordingly the reader will see that the safety method of this invention can be used to provide robust launch safety without operator intervention. Additionally this safety method provides nearly instantaneous protection, which can greatly enhance safety during rapid firing sequences controlled from electronic sequencers.

[0025] Although the description above contains many specifics, these should not be construed as limiting the scope of the invention but as merely providing illustrations of the presently preferred embodiment of this invention. For example, tilt detection devices may be attached to launch units at other “appropriate” places; this option may be necessary for non-rectangular shaped launch units. Mercury tilt or tip over switches can be used instead of the contact switches described. Other types of tilt sensing devices could be used. The launch circuit can control electrical igniters, fiber optic ignition devices, pneumatic launch devices or any other electronically controlled launch device. Although the schematic drawings (FIG. 1 and FIG. 2) imply use of a negative ground system, a positive ground may be used with this method by changing the appropriate components.

[0026] A “tension fuse” could be used. For the purpose of this discussion, a “tension fuse” is defined as portion of a conductor that can easily be pulled apart, thereby, interrupting electrical continuity. A tension fuse can be a section of wire that has less tensile strength than a normal section of wire. It can be a section of wire that is replaced with a male/female slip connector pair. A tension fuse can be used as a tilt detection device. This can be accomplished by fastening the conductor on one side of the “tension fuse” to the launch surface and fastening the other side of the conductor, on the other side of the “tension fuse”, to a part of a launch unit. If the part of the unit moves or tilts away from the fixed location on the launch surface, the “tension fuse” would be broken. This could be used to break continuity of the ground loop for the launch group.

[0027] As can be seen, this method, if properly used, can provide significant safety improvement for launching pyrotechnic devices.

[0028] Thus the scope of invention should be determined by the appended claims and their legal equivalents, rather than by the examples given. 

I claim:
 1. A method of providing safety for pyrotechnics launch devices comprising the steps of: (a) providing at least one tilt sensing device per launch device, (b) providing a means of attaching said tilt sensing device(s) to pyrotechnic launch devices, (c) providing a means of disabling launch devices when one or more of said tilt sensing devices detects a tilt in the launch device beyond its tolerance, (d) disabling launches from launch devices when one or more of said tilt sensing devices detects a tilt in the launch device beyond its tolerance.
 2. The method of claim 1 wherein said tilt sensing device is a contact switch.
 3. The method of claim 1 wherein said tilt sensing device is a mercury switch.
 4. The method of claim 1 wherein said tilt sensing device is a portion of a conductor with less tensile strength than the rest of the conductor.
 5. The method of claim 1 wherein said tilt sensing device is a male/female slip connector pair. 